This is the rubber tubing insert that goes in the center of the rub rail. For newer Bullet boats that came factory with this style rail, you will need the smaller size and can choose between black and red. If you have a Bullet boat that has a rope style rub rail; you can upgrade to the rubber insert but need the larger size, only available in black. All orders will come with enough material to do any of model of Bullet Boat. Please designate size and color below. If you are unsure about which one to order, please don't hesitate to call us at Bullet Boats 865-577-7055.